基于磁场调制的磁流体动力学角速度传感器

Magnetohydrodynamics Angular Rate Sensor Based on Magnetic Induction Modulation

为改善磁流体动力学角速度传感器输出信噪比,提高传感器的测量分辨力,提出了一种基于磁场调制的磁流体动力学角速度传感器。采用交变磁场作为载波信号对输入传感器的角速度信号进行调幅,设计了磁路、μV级微弱信号预处理电路和数字相敏检波系统。仿真与实验结果表明设计的磁路能够产生幅值恒定的交变磁场,磁感应强度有效值和均匀性满足传感原理需求,电路仿真结果表明预处理电路可有效规避低频噪声干扰,数字解调系统提取信号后,信号频率误差小于0.6%,幅值误差小于0.15%。

In order to improve the output SNR and the measurement resolution of the magnetohydrodynamics angular sensor,a magnetohydrodynamics angular rate sensor based on magnetic induction modulation is proposed.We use the alternating magnetic induction as the carrier signal to modulate the amplitude of the input angular rate signal,and design the structure of its magnetic circuit,μV-level weak signal preprocessing circuit and digital phase sensitive detection system.The simulation and experimental results show that the designed magnetic circuit can generate alternating magnetic field with constant amplitude.The effective value and uniformity of magnetic induction intensity meet the requirements of sensing principle.The circuit simulation results show that the preprocessing circuit can effectively avoid low frequency noise interference.The relative error of signal frequency is less than 0.6%and the relative error of the amplitude is less than 0.15%after the signal was extracted from the digital phase sensitive detection system.